The present invention relates to a product management system and, more particularly, to a product management system in which radio frequency identification (RFID) tag technology is utilized to monitor and report the amount of product left in a container or to monitor weight or pressure with respect to a product.
An RFID tag is an object that can be applied to or incorporated into a product for the purpose of identification using radio waves. The RFID tag can be read remotely by an RFID reader without contacting the RFID tag.
Most RFID tags contain at least two parts. One part is an integrated circuit for storing and processing information, modulating and demodulating an RF signal, and other specialized functions. The second part is an antenna for receiving and transmitting the signal.
Today, a significant thrust in RFID use is in enterprise supply chain management whereby the efficiency of inventory tracking and management of the supply chain are improved.
It would be desirable to improve the art of using RFID for inventory management by identifying and/or tracking the contents of product containers and the amount of product left in those product containers. For example, products that are sold through supermarkets, such as milk, baby formula, laundry soap, medicines, personal care items, and the like, are consumed regularly, and often the inventory of those products can be depleted by the consumer prior to acquiring additional inventory from the supermarket. Consequently, a state of need and/or discomfort is experienced due to the delay in replacing products and often the need to minimize replacement time increases replacement cost. It is often critical to plan product replacement in advance of need in order to avoid the state of need and/or discomfort, as well as, to minimize replacement cost.
It would be desirable to have a product management system which can function at a low operating cost and with a high degree of convenience. Components of the proposed system need to provide the product management function and yet be low cost to the point of being disposable in order to be cost effective enough to be incorporated into everyday packaging and/or products.
Various solutions have been proposed for product management.
Chishima et al. U.S. Patent Application Publication No. US2006/0119484, the disclosure of which is incorporated by reference herein, discloses in FIG. 2 a weight sensor for determining the weight of the contents in a container. A radio reading device in the lid of the container reads the RFID tag on the package which is to be inserted in the container. Chishima et al. further discloses in FIGS. 5 and 6, a transmitter and receiver for estimating the remaining amount of liquid in the container by transmitting radio waves from the transmitter in the top of the container to the receiver in the bottom of the container and then measuring the attenuation of the radio waves to result in an estimation of the amount of liquid left in the container. The transmitter and receiver may be driven by an RFID tag (transmission device) on the side of the container.
Newman U.S. Pat. No. 4,254,482, the disclosure of which is incorporated by reference herein, discloses in FIG. 1 an echolocation arrangement in which a transducer 16 emits and receives sound waves in order to determine the level of a flowing liquid or of material level in a closed container.
Schackmuth et al. U.S. Patent Application Publication No. US2007/0254080, the disclosure of which is incorporated by reference herein, discloses an inventory management system for a restaurant in which a plurality of food items are placed on a tray and the weight of the tray is monitored by a weight sensor and further an RFID tag is attached to the tray to provide information on the type and quantity of food items on the tray. The trays may be temporarily stored in a food holding cabinet which may contain an RFID interrogator (reader) for reading data from the RFID tag.
The use of RFID tags attached to products is quite common for the purposes of inventory tracking, product expiration, product identification and so on. However, there does not appear to be any attempt to utilize RFID tags to internally monitor the loose contents or fill level of the product container.